WASHINGTON -- The use of silicone gel breast implants will be severely restricted for cosmetic purposes but allowed for women seeking reconstructive surgery, the Food and Drug Administration said on Thursday.

The devices will no longer be available on the general market, and all women who receive them will do so only as participants in scientific studies designed to answer unresolved questions about their safety, the FDA said.

``The manufacturers have not shown these devices to be safe,`` FDA Commissioner David A. Kessler said at a news conference.

The announcement marked the final chapter of a nearly yearlong emotional national debate over the fate of the controversial devices.

The decision, which closely followed the recommendations made by an FDA advisory committee in February, reflected an effort to reconcile concerns about the known and suspected dangers of silicone with the feeling that some women, particularly breast cancer patients who have undergone mastectomies, have a compelling psychological need for the devices.

Dr. Norman Cole, president of the American Society for Plastic and Reconstructive Surgery, called the FDA decision ``the first sign that science, logic and compassion are being returned to the review process for these devices,`` and said he was relieved that women with the most pressing need for the devices would be able to have them.

But ``we continue to be disappointed that the government has placed itself in the role of judging the morality of a woman`s reasons for choosing breast implants. The needs of women who seek augmentation of their breasts are poorly understood by those who do not share this desire.``

Ann Marcou, co-founder and director of counseling for Y-ME, a national information and support network for women with breast cancer, called the FDA`s action ``just about the best decision that could have been made. It`s really what I would call a compassionate decision. It helps women with breast cancer, who are in a terrible dilemma, and also establishes a basis to collect some solid scientific research.``

Kessler urged breast cancer patients seeking reconstruction to consider all available options, including the use of saline implants and a more complicated surgical procedure that involves using tissue from another part of the body to reconstruct the breast.

FOR QUESTIONS

The FDA said there was no need for women to have their implants removed if they were not experiencing problems, but urged them to undergo periodic checkups and call the FDA toll-free hotline if they had any questions. The number is 1-800-532-4440. The number for hearing impaired is TTI 1-800-688-6167. The hotline operates Monday through Friday between 10 a.m. and 8 p.m.